There may be gems about Jane Austen’s life and times buried in a memoir handwritten by her older brother – but it is proving difficult to decipher his tricky handwriting.

So museum curators at her old cottage in the Hampshire village of Chawton are asking Austen enthusiasts across the world if they can help transcribe the newly acquired 78-page document.

The head of collections, interpretation and engagement at Jane Austen’s House, Sophie Reynolds, said: “It’s really, really, rare to have new Austen family material come to light. It’s not fully known what is in there so that’s really exciting.”

As well as the unpublished handwritten biography, the museum has bought an album of watercolours and drawings Austen’s brother made during his career in the Royal Navy. Both have gone on display in an exhibition called Travels with Frank Austen – the name he was known by.

Anyone who wants to help can email the house to request a page to transcribe. Reynolds compared it to a citizen science project. “It’s genuinely useful, it’s a really valuable thing to do. Reading it is quite painstaking.”

The memoir is written in the third person and the pages towards the end of the book are particularly difficult to read as arthritis made the author’s handwriting go “spidery”.

Reynolds said: “Jane Austen left so little facts on her life. This is another piece of the puzzle that can go into the museum. Scholars will find it fascinating to pull things out. It’s about filling in some more of the details that sort of surrounded her. We can see the world a little bit as she would have done.”

Austen lived at Chawton for the last eight years of her life and wrote Pride and Prejudice, Sense and Sensibility, Mansfield Park, Emma, Northanger Abbey and Persuasion there.

Both the manuscript biography and the watercolour album came up for auction at Bonham’s in London last June and were acquired by Chawton with funding from Friends of the National Libraries, a charity that saves the nation’s written and printed heritage.